Keywords

Introduction

Since ZnO nanoparticles (ZnO-NPs) exhibit strong antibacterial activities on a broad spectrum of bacteria the aim of this study was to evaluate the antimicrobial activity of Zno-NPs against Pseudomonasaeruginosa as a model for gram-negative bacteria.

Methods

The average size of Zno-NPs was 20 nm, as determined through scanning electron microscopy. Muller Hinton broth was used as a growing medium for Pseudomonasaeruginosa. Photocatalytic experiment was carried out in a laboratory-scale batch reactor with low pressure ultraviolet irradiation (380 nm). Different experimental parameters such as amount of Zno-NPs, contact time, inorganic and organic substances and pH on photocatalytic inactivation of Pseudomonasaeruginosa cells have been studied. An initial Pseudomonasaeruginosa concentration of 108 CFU/mL was used for all experiments.

Results

Result showed that, almost all the initial Pseudomonasaeruginosa cell (108 CFU/ml) was inactivated in 60 min in the presence of 2 g/l ZnO-NPs. Photocatalytic inactivation of bacteria was found to follow first order kinetics. The initial pH of the water did not play an important role on the inactivation rate within a range of 6–8 pH units. The amount of photocatalyst also plays an important role in photocatalytic inactivation rate. As the result showed increasing the photocatalyst amount provided more rapid inactivation.

Conclusion

Addition of some inorganic ions to the suspension affects the sensitivity of Pseudomonasaeruginosa and caused to retard the inactivation rates. Since the sensitivity of Pseudomonasaeruginosa to photocatalytic treatment was fairly good, it is therefore, recommended to use this nano-particle for water treatment.

Copyright

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.